Messages

21

General Mach Discussion / Re: Limit switch issues

« on: December 27, 2015, 11:39:29 AM »

You can't disable the Estop, or Mach3 will not run. Just set it to any unused input pin number, and toggle the active low setting if it doesn't let you reset.

btw: I just enabled my limit switches, and home switches...now my x axis tries to home to the right (+ side) instead of the home switch on the left (- side) and it doesn't trip the limit switch when it does, it just grinds into the rail.....

when I reverse the homing, then when I jog to the plus, (right) it goes left and vice versa....

I get the abnormal condition light flashing and on the DROs it says my "head" is at -51 inches on a 24" table

This is what happens when you change too many things at one time.

First, you get the machine to move in the correct direction. If you jog to the right, do the DRO's count up (increase). If so, then Mach3 is correct. But if the machine is moving left, go to Config > Homing/Limits and check the reverse box to change direction.
Once it moves in the correct direction, then home the X axis. If it moves the wrong way, toggle the "Home Neg" setting.

Disregard the Abnormal Condition. It's the absolutely worst feature in Mach3.  When everything is working the way you want it to, go to the Operator menu, and click "Set Normal Condition". Even better is to remove it from the screen with a screen editor.

There's nothing wrong with the X home switch at the positive end of travel. I have mine setup that way, so that when the machine homes, the gantry is clear of the table so I can setup my parts.
What you want to do, though, is go to Config > Homing/Limits and enter the actual switch position in the Home Offset box. This value is what mach3 sets the DRO's to when you home. So, if you set it to 45, your X zero will be at the left end of the table. When you home, the X DRO will be set to 45.

So just to confirm, Mach3, in all it's glory, doesn't allow you to have your home at ACTUALLY 0? That it is factory set at +24 (in my case) which is the far right of the table? that I have to trick it to think that X0 by putting in a positive number to get it to go to zero? You see, this is counterintuitive to me....if I want my x axis to move to zero, I should be able to put zero in my home position and to get it to be there, I feel I should have to put in a NEGATIVE number (if mach is saying dammit jim, 0 is at +24....).....to get it to be 0....

22

General Mach Discussion / Re: Limit switch issues

« on: December 27, 2015, 11:29:25 AM »

If you're interested, I can explain

a) Why, after a limit has been hit, there is good reason why Mach3 allows a careless user to jog or move further onto the tripped limit.
b) why, it is a perfectly reasonable option to have a machine set to home to back left rather than front left.
c) why you most likely don't need to re-wire anything or move any switches on your machine and yet still have it do whatever you like.
d) last and probably least, why the ftp links in this thread are "dead".

sure go ahead...

a) Mach3 was designed to be fully functional with just ONE parallel port. It therefore has just 5 inputs. With just ONE input you can have fully functional limit protection AND homing.

How many inputs do you suppose you'd have to sacrifice just in order for Mach3 to prevent a careless user from jogging the wrong way after a limit trip?

b) Using a 3 axis setup as an example, home does not have to be 0,0,0. It can be any coordinate you like. Having it at the back means on an X gantry machine the gantry is not obscuring the table.

c) Limits can be wired series where they use just one input or in parallel where they can use as many inputs as you have switches if you so choose. Is there any point in the latter? absolutely none. Functionality will be identical.

However you can also use some of those switches to double as homing switches. If you stick with series, all will work just fine but homing will be done sequentially. If you wire parallel then you can choose to set up so axes home concurrently.

d) ftp links do not start with http.

1)that doesn't explain why a user would want to move one or more of their axis past the limit switch where by doing so, they will damage their machine.
2)but your "home" should be 0,0,0 on the table, not (in my case) 0,48,0. Once zero'd in, you can move the gantry anywhere you like.
3) funny, mine are wired in parallel and yet home consecutively.....if I understood why you write, they should all home at the same time.....
4) but ftp links are a web address....

My reason for wanting my home at 0,0,0 is because during some 3D long program runs (I have some that take upwards of 12 hours) occasionally a problem will occur and I'll lose "home"....to start machining a 3D items from scratch to reestablish zero is crazy. Re-homing my machine manually (to locate the 3 axis on one spot) more likely than not will result in the 3D item being machined to have parts of it slightly offset than the rest....for eg: if I'm cutting a nose of an animal, if I'm .01 of an inch off, instead of being smooth, the nose bottom and top will be misaligned.

One of the things that occurs is, where I live, the electrical grid is as fragile as a robin's egg. Whenever it is raining, windy, snowing, (and sometimes) sunny, or just because it's thursday, the power will flicker...when it does, even for a millisecond, that causes the machine, and mach3 to become out of sync.....it's gotta so bad I have to check the weather report if I have to run a long highly detailed item...if it's windy? I don't run. If it's snowing? I don't run often times I HAVE to run it on that particular day (due to scheduling) so I'll wait and run it at 12 am after the storm or whatever has passed.....

Yes, I can re-zero manually and it's pretty simple if you're using a 30 deg v engraving bit...but if you're using a ball mill, or a 1/4" 2 flute roughing bit, it could take an hour of trial and error to get it back close, then after the program run is over, 9 times out of 10, alignment is off....

23

General Mach Discussion / Re: Limit switch issues

« on: December 27, 2015, 06:58:03 AM »

btw: I just enabled my limit switches, and home switches...now my x axis tries to home to the right (+ side) instead of the home switch on the left (- side) and it doesn't trip the limit switch when it does, it just grinds into the rail.....

when I reverse the homing, then when I jog to the plus, (right) it goes left and vice versa....

I get the abnormal condition light flashing and on the DROs it says my "head" is at -51 inches on a 24" table

btw, I disabled the e stop, on pin 10 due to the conflict..clicked ok....went back, it was selected again......ayup, Mach3 is easy...easy as tuning a bugatti veyron w10 lol.....

24

General Mach Discussion / Re: Limit switch issues

« on: December 27, 2015, 06:55:02 AM »

If you're interested, I can explain

a) Why, after a limit has been hit, there is good reason why Mach3 allows a careless user to jog or move further onto the tripped limit.
b) why, it is a perfectly reasonable option to have a machine set to home to back left rather than front left.
c) why you most likely don't need to re-wire anything or move any switches on your machine and yet still have it do whatever you like.
d) last and probably least, why the ftp links in this thread are "dead".

sure go ahead...

25

General Mach Discussion / Re: Limit switch issues

« on: December 27, 2015, 04:58:39 AM »

That's what it shows on the PDF. Have you a multimeter at hand, so you can check voltages and switches as you work through each switch. What you are looking for (and I am sure someone more experienced than me will correct me) is 5v between +5v and pin 10, when a limit switch is pressed this should drop to 0v, then return to 5v when the switch is released i,e, a low signal, which is what Mach3 is looking for if configured correctly.

Yes and Yes...that is what should happen if pin 10 is ground....you can also test this via a ohm meter...the resistance should be low when the switch is closed, and 100% or more when open.....btw, I should have thought of testing it myself.....DOH......the mind is a terrible thing to waste.....

26

General Mach Discussion / Re: Limit switch issues

« on: December 27, 2015, 04:57:22 AM »

WOW!, what a thread

OP - you say you have CNC experience but do you have CNC machine building experience?? There is a world of difference here and from reading this thread it seems you do indeed know your CNC but not how to build one, just my presumption from the difficulties you are having with how the switches work. In a pre-built machine all this config work is done for you and the $$$$ go up, in DIY you do it yourself and the $$$$ stay down but you have to learn the intricacies of the system in use, think yourself lucky that the machine does use Mach3 and not one of the exotic flavours out there - Mach3 is probably the most flexible and easy to configure system going.

2 years ago I knew 100% of nothing about CNC, Mach3, G-Code or building a plasma cutter, 2 years later I have built two CNC tables and successfully made money out of both (for my own use). Yes I did struggle a lot at the start but the guys on here got me through.

You nailed it, I am a user, not a builder....(I believe I said that early on but anyways)....when I started out 15 years ago, I drew products in autocad, loaded them into an app that converted the drawings to gcode, loaded them into the CNC zeroed it, and ran the program....didn't have to worry about the estop, limit switches configuration nothing...

Then when I decided to get a cnc of my own, (cabinet maker) I looked into building and seeing as how it was WAY over my head, I looked at buying a complete system. I looked into $10,000 state of the art systems, outside my price. I saw systems for $1000, err no an idiot pays too much but a fool pays too little. Looked around for machines in the size I needed, found one, talked to the guy, watched videos and photos, and bought a turn key system...OOPSY no it wasn't .....nothing worked the way the 4 or 5 other machines I have used...

Spent 2 hours on the phone, it kind of worked, at least enough so that I could use it....and from then on, I worked around the issues..

The reason I am addressing this NOW is because I'm going to be replacing the BOGUS plastic structural parts with aluminum and replace all the BOGUS design flaws in the machine....Where I got screwed was in the photos and videos, the black parts looked like anodized aluminum....oopsy, no, they are NYLON and I can see the fricken gantry flexing when I run programs.....hell, 2 years ago I replaced, I ********* you not, the PLASTIC gear racks and pinions with STEEL....yes, that's right, PLASTIC gears....(don't laugh) but my 2 x 4 machine was slowly becoming a 2" x 4" machine because I kept breaking teeth.....

I thought I should get the software and electronics sorted before going ahead with the mechanical improvements....I'm doing this now because this is normally a very slow time for me and it took a beating before Christmas, I made about 6 months worth of business in 7 weeks.....

27

General Mach Discussion / Re: Limit switch issues

« on: December 27, 2015, 04:48:52 AM »

Google C10 PARALLEL PORT INTERFACE CARD and the first result is the PDF for your board, your answer is there................................It does say connect to +5v and corresponding pin. But again read the information, it will help you understand how it all works.

yeah, see, I would never consider a "pin" to be ground...to me, "ground" is the frame of the machine or a grounding terminal on the board....so if I understand this correctly, I would be connecting the limit switches to pin 10 and 5V terminals?

28

General Mach Discussion / Re: Limit switch issues

« on: December 27, 2015, 04:19:53 AM »

By all means move the switch, by all means rewire them so they are in series, just remember to wire them to the correct terminal on the board and set the pins correctly, (10) for your limits and (13) for your E stop, in mach3. There is no danger of magic smoke being released if you do this, unless of course you decide to wire it to mains voltage, but that would be just silly......................................but we all do silly things........................................especially when we are tired!!!!!!!

that's what I figured being as how it is only 5 volts but I've made "magic smoke" before thinking that "hey, what could go wrong"? (but that's hilarious, magic smoke, I'm going to remember that lol)

One other question: on my board: there are two terminals: 5V and a pin number....I should just wire them to pin 10 and ignore the 5v (which they are currently wired to)?

29

General Mach Discussion / Re: Limit switch issues

« on: December 27, 2015, 04:02:46 AM »

Hi Mike,

Looking at your .xml file I notice that you do not have limit switches enabled – only home switches are enabled.
There is also a conflict (not serious but it should be avoided if possible) where X Home and EStop share the same LPT pin number 10. You also need to assign a port# to EStop.

Just to draw your attention to the relevant section of the manual…
• If you implemented configuration two from Section 4.5, you will probably have Home switches on the X, Y, and Z axes. Enable the Home switches boxes for these axes, and define the Port/Pin to which each is connected. If you are combining limits and the Home switch as one signal, then you should enable Limit --, Limit ++, and Home for each axis and allocate the same pin to Home, Limit --, and Limit ++.


Tweakie.

Thanks, I noticed that a little earlier this evening....(like maybe 20 minutes ago lol) and since I'm at my design computer (because my cnc computer isn't connected to the net) I haven't enabled them yet...this is after I learned that one switch could be used as a limit switch and a home switch.....

Thanks for the Estop issue....how do I go about assigning a different pin to estop and a port? Frankly, I haven't used Estop in 6 years so if it is completely disabled, I wont' sweat over it....

As I'm reading through the steps to set up the switches, this is one thing that drove me to fury with the company that made my cnc....They have installed the Y home switch at 48" NOT at 0 (my table is 24" x 48"). When I contacted the manufacturer and said why is it there? that is ridiculous and how do I go about moving it to the correct location?

His answer? You dont' want to do that...
My response: why?
His answer: you just dont'

ARRRGHHHHH so for the past 4 years (took me two years to get frustrated enough to pursue it) I've been manually homing my machine because the _____ head won't give me a clear straight answer.....

Anyhow, (this is a question for all):

Is there any "danger" of burning out anything if I disconnect all my switches and wire them in series before changing the settings in Mach3?

I tell you, the first thing tomorrow (actually later on this morning after I too get some "kip" is to physically move that @%^&%#^% limit/home switch to where it should have been all along.....

30

General Mach Discussion / Re: Limit switch issues

« on: December 27, 2015, 02:57:05 AM »

mother in law? for new years? I'd rather read the mach 3 manual lol

that's a dead link again.....